As an epidemic of asthma left more and more children wheezing
during the
past two decades, scientists blamed everything from obesity to
cockroach
droppings to the way we build our houses.
Now, researchers from Brigham and Women's Hospital have
identified another
potential cause: child abuse.
The Brigham doctors discovered that children in Puerto Rico who
endure
physical or sexual abuse are twice as likely to suffer from asthma
as
youngsters who do not face maltreatment. Abuse, the researchers
found, was
a more powerful predictor of whether a child would develop asthma
than if a
family was rich or poor.
Stress has recently been implicated as a trigger for asthma. And
the Boston
researchers said they believe that the extreme strain caused by
abuse - and
the hormonal changes that result - may predispose children to worse
bouts
of the disease, which ignites chest-rattling coughs and chronic
shortness
of breath. It is believed to be the first time researchers have
established
a possible link between child abuse and asthma.
"It certainly seems biologically plausible, particularly
considering that
it's hard to think of any more stressful circumstance for a child
than
physical or sexual abuse, especially when that abuse comes from
within the
family," said Dr. John Heffner, a past president of the American
Thoracic
Society who was not involved with the research but is familiar with
it.
The Brigham scientists, who collaborated with specialists from
Columbia
University and the University of Puerto Rico, focused on Puerto
Rican
children because they are more likely to have asthma and to die
from the
disease than any other US youngsters, regardless of whether they
live on
the island or the mainland.
Roughly 25 percent of Puerto Rican children are diagnosed with
asthma at
some point during childhood, compared with 13 percent of white,
non-Hispanic children and 16 percent of black youngsters.
"The question is, why?" asked Dr. Juan Celed?n, a lung
specialist in
the Brigham's Channing Laboratory. "Is this heredity? Is this
environmental factors? Is this some behavioral or lifestyle
factor?"
The researchers questioned about 1,200 children and their
parents. Before
they agreed to participate in the study, families were told that
some
questions would pertain to abuse and that authorities would be
alerted if a
child reported having been struck violently or subjected to sexual
abuse.
Asthma was significantly more common among children who said
they had faced
abuse in the previous year, with 20 percent suffering from the
respiratory
ailment. Among children who had not sustained abuse, the asthma
rate was
11.5 percent.
Still, abused children represented only a small fraction of the
total
number with asthma.
"It's very clear it's a very complex disease," Celed?n said.
"By no
means should we say abuse is responsible for a majority of the
cases. And I
don't want this to stigmatize Puerto Ricans or other parents who
have
children with asthma."
From previous studies, the researchers knew that people who
suffer abuse
have depleted supplies of a pivotal hormone called cortisol that is
regulated by the brain. That's relevant to asthma because cortisol
helps
reduce inflammation, and asthma causes airways to become furiously
inflamed.
"We're not surprised that when we're frightened, our heart rate
goes up,"
Heffner said. "So we shouldn't be surprised when organs, like the
lungs,
fail or malfunction through acute or long-term stress in the
brain."
The study, Celed?n said, was not designed to definitively answer
this
crucial question: Was abuse actually triggering asthma? Conversely,
it's
possible children were more likely to be abused because they had
asthma,
making them more vulnerable. And the study's conclusions can't
necessarily
be extrapolated to all youngsters.
Still, Celed?n and Heffner said the findings are sufficiently
concerning
that doctors should take heed of them. When treating a child who
has been
abused, physicians should screen for asthma. And when a child has
recurrent, persistent, hard-to-treat asthma, Heffner said, doctors
should
consider looking for evidence of abuse.
"This is basically saying stress, violence, events that are
very traumatic
may worsen asthma," Celed?n said, "and we should continue looking
for
it."
Stephen Smith can be reached at stsmith@globe.com.
c.2008 The Boston Globe